Amazon Linux 2023 Security Advisory: ALAS2023-2026-2040
Advisory Released Date: 2026-08-04
Advisory Updated Date: 2026-08-04
FAQs regarding Amazon Linux ALAS/CVE Severity
BIND may accept incorrect child-zone NSEC3 records as valid, which could allow an attacker to forge authenticated NXDOMAIN responses.
This issue affects BIND 9 versions 9.18.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1. (CVE-2026-10723)
If BIND encounters a particular invalid data structure in a DNS record, it will accept the invalid data, and may subsequently abort and exit.
BIND will first need to store a DNS record for a key (KEY, DNSKEY, etc.). That key must specify a PRIVATEDNS algorithm (253), and in the algorithm identifier, improperly give a length longer than the actual identifier data. The invalid identifier will be stored. If BIND later needs to render that record to text, it will use the invalid length during processing, leading to a consistency check failing.
This issue affects BIND 9 versions 9.18.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, 9.18.11-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1. (CVE-2026-10822)
An attacker who knows (or guesses) that a resolver uses RPZ with wildcard CNAME policies can craft query names long enough to trigger a NAMETOOLONG error condition during RPZ processing. This is not handled correctly and may lead to defeating the RPZ rule. It also may lead to an unexpected exit of the BIND 9 software.
This issue affects BIND 9 versions 9.16.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, 9.16.8-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1. (CVE-2026-11331)
A DNSSEC validating resolver that is under a random subdomain attack against a DNSSEC-signed zone can suffer from runaway memory usage. The attacker needs to be able to send queries faster than the resolver can perform validation. The increased memory usage can be orders of magnitude beyond the limit configured in the `max-cache-size` parameter.
This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1. (CVE-2026-11622)
It is possible for an attacker's zone to respond to a query with an RRSIG that has a smaller number of labels than the zone in which the RRSIG is contained. This causes `named` to produce a wildcard name for a zone that is shorter than the attacker's zone, which can result in cache poisoning. For this attack to have any effect, the resolver under attack must have set `synth-from-dnssec yes;` (which is the default).
This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1. (CVE-2026-11721)
The issue is unexpected program termination based on ordering and/or specific content in responses to queries for CNAME or DNAME, and A records. Specifically, if a client queries for a DNAME and A record below the DNAME to the resolver, and the authoritative server responds positively to the A query but delays the DNAME response and later responds negatively, `named` may quit unexpectedly. Or, if a client queries for a CNAME and A record for the same name to the resolver, and the authoritative server responds positively to the A query but delays the CNAME response and later responds with a self-referential CNAME, the same failure may occur.
This issue affects BIND 9 versions 9.18.0 through 9.18.50, 9.20.0 through 9.20.24, 9.18.11-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1. (CVE-2026-12617)
If a provably insecure domain is covered by both an NSEC and NSEC3 record at the parent, and there exist an RRSIG for only one of these types, then BIND may exit unexpectedly with an assertion while validating this proof.
This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1. (CVE-2026-13204)
The BIND resolver accepts validly-signed NSEC records where the "Next Domain Name" field points outside the signer's zone.
This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1. (CVE-2026-13321)
Affected Packages:
bind
Issue Correction:
Run dnf update bind --releasever 2023.12.20260803 or dnf update --advisory ALAS2023-2026-2040 --releasever 2023.12.20260803 to update your system.
More information on how to update your system can be found on this page: Amazon Linux 2023 documentation
aarch64:
bind-libs-debuginfo-9.18.50-1.amzn2023.0.2.aarch64
bind-debuginfo-9.18.50-1.amzn2023.0.2.aarch64
bind-9.18.50-1.amzn2023.0.2.aarch64
bind-debugsource-9.18.50-1.amzn2023.0.2.aarch64
bind-libs-9.18.50-1.amzn2023.0.2.aarch64
bind-utils-9.18.50-1.amzn2023.0.2.aarch64
bind-dnssec-utils-9.18.50-1.amzn2023.0.2.aarch64
bind-utils-debuginfo-9.18.50-1.amzn2023.0.2.aarch64
bind-devel-9.18.50-1.amzn2023.0.2.aarch64
bind-dnssec-utils-debuginfo-9.18.50-1.amzn2023.0.2.aarch64
bind-chroot-9.18.50-1.amzn2023.0.2.aarch64
noarch:
bind-license-9.18.50-1.amzn2023.0.2.noarch
bind-doc-9.18.50-1.amzn2023.0.2.noarch
src:
bind-9.18.50-1.amzn2023.0.2.src
x86_64:
bind-libs-debuginfo-9.18.50-1.amzn2023.0.2.x86_64
bind-dnssec-utils-9.18.50-1.amzn2023.0.2.x86_64
bind-devel-9.18.50-1.amzn2023.0.2.x86_64
bind-debuginfo-9.18.50-1.amzn2023.0.2.x86_64
bind-utils-debuginfo-9.18.50-1.amzn2023.0.2.x86_64
bind-debugsource-9.18.50-1.amzn2023.0.2.x86_64
bind-dnssec-utils-debuginfo-9.18.50-1.amzn2023.0.2.x86_64
bind-libs-9.18.50-1.amzn2023.0.2.x86_64
bind-utils-9.18.50-1.amzn2023.0.2.x86_64
bind-chroot-9.18.50-1.amzn2023.0.2.x86_64
bind-9.18.50-1.amzn2023.0.2.x86_64